Container and method of forming the same



Filed Aug. 7, 1961 INVENTOR. KARL W/LL/AM ///1VE ATTOE/VE'Y 3,142,280Patented July 28, 1964 3,142,280 CONTAINER AND METHOD OF FORMING THESAME Carl William Heinle, Short Hills, N.J., assignor to American CanCompany, New York, N.Y., a corporation of New Jersey Filed Aug. 7, 1961,Ser. No. 129,775 3 Claims. (Cl. 113121) The present invention relates toimprovements in easyopening containers of the type wherein a singlescore line is formed in the cover skirt in order to provide a tearingstrip which may be torn away to eliminate the locking connection betweenthe cover and the container body and thereby permit removal of thecover.

Containers of this general type have been long known in the art but havenever attained very great popularity. However, with the recent trendtoward the use of aluminum in containers, interest in this general typeof container has been revived because of the fact that when thiscontainer cover is made of aluminum, it may easily be torn along thescore line manually without requiring the use of a key.

In the usual version of this container, the tearing strip is formed inthe cover flange prior to the time the flange is crimped onto thecontainer body. As a result, there is the definite danger that thispreformed score line will crack during the seaming operation. Thepresent invention contemplates a method of overcoming this problem byforming the score line during the seaming operation so that a preformedscore is not required. As an additional feature, the inventioncontemplates a seaming operation wherein both the cover flange and thebody wall immediately inwardly of it are simultaneously deformed toprovide interlocking grooves which secure the cover in place on thebody. This eliminates the need for providing the body with a lockinggroove prior to the seaming operation.

An object of the invention therefore is the provision of an improvedmethod of forming an easy open tear strip container.

A further object is the provision of a method of forming a scored tearstrip in the depending skirt of a cover during the seaming operation.

A still further object is the provision of a container formed byutilization of the instant method invention.

Referring to the drawings:

FIGURE 1 is a side elevational view of an easy-opening container formedaccording to the method of the instant invention;

FIG. 2 is a fragmentary vertical section on an enlarged scale takenthrough the upper portion of the container of FIG. 1 and showing theperipheral body and cover portions as they appear prior to the seamingoperation;

FIG. 3 is a view on an enlarged scale of the upper portion of thecontainer of FIG. 2 after the completion of the combined seaming andscoring operations, the view also showing in cross section a portion ofthe combined seaming and scoring roll and the seaming chuck whichcooperate to perform the method steps of the instant invention;

FIG. 4 is a fragmentary section taken substantially along the line 4-4of FIG. 3;

FIG. 5 is a vertical section similar to FIG. 3 but showing the inventionas utilized in conjunction with a slightly different form of containerconstruction.

As a preferred and exemplary embodiment of the instant invention, FIG. 1discloses an easy opening container which has been formed by the methodof the instant invention. The container includes a cylindrical tubularbody which comprises a body wall 11 and a bottom end closure 12. Thebody wall 11 may be made of any suitable thin metal such as aluminum ortin plate and may be formed with or without a side seam. It may also beformed of fibre or plastic. If desired, the body 10 may comprise aone-piece drawn shell of metal or other suitable material.

The top end of the body 10 is closed by means of cover 14 whichpreferably is formed of an easily tearable metal such as aluminum, butwhich also may be formed of other suitable materials such as tin plate,etc.

As seen in FIG. 2, the upper end of the body wall 11 is initially curledoutwardly and then extended downwardly to form an open hem 16 which isspaced outwardly from the main body wall 11.

The cover 14 is provided with a depressed countersink panel 17 which atits outer edge is bent upwardly to form a countersink wall 18 which isformed with a central step 20, a lower wall portion 22, and an upperwall portion 24, the wall portion 24 being somewhat larger in diameterthan the wall portion 22. At its upper end the countersink wall 18 iscurved outwardly and then downwardly to form a downwardly extendingskirt or flange 26 which is spaced slightly away from the body hem 16when the cover is inserted in the open mouth of the body 10 preparatoryto the seaming operation, as seen in FIG. 2. If a hermetic seam isdesired in the sealed container, the interior surface of the cover skirt26 is lined with a thin film of a suitable resilient lining compound 28.

In carrying out the method steps of the instant invention, the cover 14is positioned on the body 10, and a seaming chuck 36 is then insertedinto the cover 14. The seaming chuck 36 is provided with an annular step38 so that its lower and upper portions fit snugly against the steppedwalls 22, 24 of the cover 14. After the seaming chuck 36 has thus beenpositioned, the cover skirt 26 is rolled inwardly by the upper portion49 of a circular seaming roll which is pressed into pressured contactagainst the skirt 26 in any suitable manner. As a result of the inwardpressure exerted by the seaming roll R the upper portion of the coverskirt 26 is pressed against the body hem 16 and the latter is collapsedinto engagement against the upper portion of the body wall 11 to form aclosed hem as seen in FIG. 3. The lining compound 28 which is carried bythe cover skirt 26 is compressed between the skirt 26 and the hem 16 toform a hermetic seal. Simultaneously with this collapsing operation, thelower portion of the cover skirt 26 and the inwardly adjacent portion ofthe body wall 11 are deformed inwardly into the annular space 30 whichis disposed between the cover wall portion 22 and the body wall 11 by anoutwardly extending annular bead or projection 42 which is formed in thelower portion 44 of the seaming roll R (see FIG. 3).

The rolling action of the head 42 produces an indentation or groove 46in the cover skirt 26 and a cooperating indentation or groove 48 in thebody wall 11. As a result of the locking action of these interfittinggrooves 46, 48, the cover 14 is firmly secured to the upper end of thecontainer body. It will be obvious that this seaming method will alsowork effectively when the body 10 is formed of fibre or other softstock, for in such case the cover head 46 will compress the material ofthe body wall and embed itself therein.

It has been found that a body wall 11 made of single thickness stock canbe readily deformed by the seaming projection 42. In the event the bodywall 11 is formed with a multi-layered side seam (not shown) which wouldbe difficult to groove during the seaming operation, it may be desirableto pre-groove the side seam area in alignment with the subsequentlyrolled grooves 46, 48 in order to insure that the grooves 46, 48 extendacross the side seam in the finished container.

In order to permit the easy removal of the cover 14 from the containerbody 10, a circumferential score line J 50 is rolled into the coverskirt 26 during the seaming operation in order to form the bottom,grooved portion of the skirt 26 into an easily removable tearing strip52. The score line 50 is produced by a scoring roll 54 which is disposedbetween the upper and lower portions 40, 44 of the seaming roll R.Preferably, the parts 40, 44, 54 are separate pieces which are suitablysecured together. The scoring roll 54 is provided with a sharp edgeportion 56 which projects outwardly beyond the adjacent wall portion ofthe seaming roll R a distance which is somewhat less than the thicknessof the cover skirt 26 so that the depth of the score line 50 isaccurately controlled. The tearing strip 52 is provided with a dependingtearing tongue 58 and a notch 60 which is disposed adjacent one end ofthe tongue 60. When removal of the cover is desired, the tearing tongue58 is grasped between the thumb and forefinger of the consumer and ispulled or twisted diagonally upwardly, to the right as seen in FIG. 1.This twisting action results in a tear which extends across the tearingstrip 52 from the apex of the notch 60 to the score line 50. Thereafterthe tongue 58 is pulled circumferentially around the container thusdetaching the tearing strip 52 from the cover 14 along the score line 50and destroying the beaded interlocking connection between the cover 14and the body wall 11. Thereafter, the cover may be readily liftedupwardly to remove it from the container body 10.

It is desirable to form the portion of the chuck 40 immediately belowthe scoring roll 54 with an annular band of narrow serrations 62, theapices of which extend outwardly to the edge of the scoring knife 52 andcreate knurlings 63 (see FIG. 1) in the cover flange 26 just below thescore line 50. These knurlings 63 have the effect of work hardening thecover stock in this area and serve to confine the line of tear to thescore line 50 and prevent it from tearing out of the score line 50 anddown into the tear strip 52 during the opening operation.

FIG. 5 shows the instant invention as applied to a modified form ofcontainer wherein the upper edge of the body wall 11 is not hemmed, thecover skirt 26 is not provided with the sealing compound, and theknurlings 63 are omitted. However, in all other aspects, the closure ofthis modified form of container is similar to that of the preferred formof FIGURES 1 and 3, inasmuch as the cover skirt 26 is indented into thebody wall 11 during the seaming operation to form cooperating lockingbeads 46, 48 and a score line 50 is formed in the cover skirt 26 tocreate a tearing strip 52.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description and it will beapparent that various changes may be made in the form, construction, and

arrangement of the parts without departing from the spirit and scope ofthe invention or sacrificing all of its material advantages, the formhereinbefore described being merely a preferred embodiment thereof.

I claim:

1. The method of forming an easy opening container, comprising the stepsof positioning a cover in the open end of a container body, said coverhaving a peripheral skirt extending over the marginal portion of saidbody adjacent said container end, rolling interlocking grooves in saidcover skirt and said marginal body portion in a seaming operation tosecure said cover and said body together, and simultaneously with saidseaming operation rolling a circumferential score line in the outersurface of said cover skirt between said interlocking grooves and saidcontainer end to create in said cover skirt a removable tearing stripcontaining the grooved portion of said skirt to facilitate opening ofsaid container.

2. The method of forming an easy opening container,'

comprising the steps of positioning a cover in the upper open end of acontainer body which is provided with an outwardly and downwardly turnedopen hem, said cover having a peripheral skirt extending downwardly fromsaid container end, pressing said cover skirt inwardly against said openhem to collapse the latter into engagement with said body, rollinginterlocking grooves in said cover skirt and said body below said hem tosecure said cover and said body together, and simultaneously with theformation of said interlocking grooves rolling a circumferential scoreline in said cover skirt above said interlocking grooves to create insaid cover skirt a removable tearing strip to facilitate opening of saidcontainer.

3. The method of claim 2 wherein a narrow annular band of knurlings isformed in said cover skirt immediately below said score linesimultaneously with the formation of said score line and saidinterlocking grooves.

References Cited in the file of this patent UNITED STATES PATENTS1,689,605 Walter Oct. 30, 1928 1,741,918 Burbank Dec. 31, 1929 1,821,157Hothersall Sept. 1, 1931 2,072,149 Young Mar. 2, 1937 2,159,325 Fabricea May 23, 1939 2,351,550 Sebell June 13, 1944 2,443,185 Erb June 15,1948 2,521,098 Sebell Sept. 5, 1950 2,902,075 Gray Sept. 1, 1959 FOREIGNPATENTS 60,656 Norway Apr. 3, 1939 261,793 Switzerland Sept. 1, 1949

1. THE METHOD OF FORMING AN EASY OPENING CONTAINER, COMPRISING THE STEPSOF POSITIONING A COVER IN THE OPEN END OF A CONTAINER BODY, SAID COVERHAVING A PERIPHERAL SKIRT EXTENDING OVER THE MARGINAL PORTION OF SAIDBODY ADJACENT SAID CONTAINER END, ROLLING INTERLOCKING GROOVES IN SAIDCOVER SKIRT AND SAID MARGINAL BODY PORTION IN A SEAMING OPERATION TOSECURE SAID COVER AND SAID BODY TOGETHER, AND SIMULTANEOUSLY WITH SAIDSEAMING OPERATION ROLLING A CIRCUMFERENTIAL SCORE LINE IN THE OUTERSURFACE OF SAID COVER SKIRT BETWEEN SAID INTERLOCKING GROOVES AND SAIDCONTAINER END TO CREATE IN SAID COVER SKIRT A REMOVABLE TEARING STRIPCONTAINING THE GROOVED PORTION OF SAID SKIRT TO FACILITATE OPENING OFSAID CONTAINER.